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排序方式: 共有215条查询结果,搜索用时 15 毫秒
1.
GIUSEPPE PERSEO MAURO GIGLI ROBERTO DE CASTIGLIONE 《Chemical biology & drug design》1987,29(4):478-485
The synthesis of TPH-13 (Glp-Glu-Lys-Pro-Tyr-Trp-Pro-Pro-Pro-Ile-Tyr-Pro-Met-OH), a tridecapeptide isolated from the skin of the South American frog Phyllomedusa rohdei, is described and alternative approaches are discussed. 相似文献
2.
RITA PEREGO LUIGIA GOZZINI EMANUELE ARLANDINI GIORGIO BOLIS ROBERTO DE CASTIGLIONE 《Chemical biology & drug design》1995,46(5):341-345
Endothelin-1 (ET), the most potent vasoconstrictor yet discovered, is a peptide containirig 21 amino acids with two intrachain disulfide bridges. With the aim of obtaining two-chain derivatives, Et was submitted to chemical and enzymatic treatments. Reaction of ET with CNBr in 70% HCOOH gave, in addition to the expected [Hse7 lactone]-7,8-seco-ET and unreacted material, a by-product whose molecular weight was 25 m.u. greater than that of ET. When the reaction mixture, after lyophilisation, was immediately quenched with NH3-saturated dry MeOH, two products could be recovered in a 5:1 ratio, both obtained by nucleophilic attack of the homoserine lactone: the expected [Hse7-NH2]-7,8-seco-ET and [Hse7]ET, resulting from competitive intramolecular reaction of the deprotonated α-amino group of the Asp8 residue. The Lys9-Glu10 bond turned out to be very resistant to enzymatic attack both by Lys-C-endopeptidase and trypsin. The 9,10-seco-ET derivative could be obtained by treatment with Lys-C-endopeptidase only by using a high enzyme/ET ratio and after a prolonged incubation time. Cleavage of the Lys9-Glu10 bond could not be achieved by treatment with trypsin, even with a high enzyme/substrate ratio. The main product was 13, 14-seco-ET, deriving from the action of chymotripsin (present as an impurity in the trypsin preparation) on Tyr13. The structure of these peptides was confirmed by amino-acid sequence analysis and fast atom bombardment mass spectrometry (FAB-MS). Nicking of the ET structure at different positions had different impact on the biological properties of the resulting derivatives. © Munksgaard 1995. 相似文献
3.
SEVERO SALVADORI REMO GUERRINI PIERO ANDREA BOREA ROBERTO TOMATIS 《Chemical biology & drug design》1992,40(5):437-444
The synthesis of pseudotetrapeptides H-Tyr-D-Ala-Phe-NH-(CH2)2-NH2 (1a), H-Tyr-D-Ala-Phe-ψ(CH2-NH)-Gly-NH2 (2a), H-Tyr-D-Ala-ψ(CH2-NH)-Phe-Gly-NH2 (3a), and H-Tyr-ψ(CH2-NH)-D-Ala-Phe-Gly-NH2 (4a), representing the N-terminal tetrapeptide sequence of dermorphin, in which amide bonds are replaced by CH2-NH bond, is described. N-acetyl-Tyr and desamino-Tyr pseudopeptide analogs (1-4b), (1-3c) are also described. The analogs were assayed in binding studies based on displacement of μ and δ-receptor selective radiolabels from rat brain membrane and in a bioassay using guinea pig ileum (GPI). Pseudopeptides in which the C-terminal (1a) or D-Ala-Phe (3a) amide bond are substituted, exhibit higher μ-affinities and μ-receptor selectivity than the corresponding Phe-Gly or Tyr-D-Ala analogs (2a, 4a). Acetyl-and desamino-Tyr pseudopeptide analogs (1-4b) and (1-3c) did not exhibit μ and δ-opioid receptor affinity at nM concentration. The relevance of the single peptide replacement and of its association to acetylation or amino group elimination of Tyr, is discussed on the basis of a receptor model for μ and δ opioids. 相似文献
4.
Wireless Ultrasound Guidance for Femoral Venous Cannulation in Electrophysiology: Impact on Safety,Efficacy, and Procedural Delay 下载免费PDF全文
DANIEL RODRÍGUEZ MUÑOZ M.D. EDUARDO FRANCO DÍEZ M.D. JAVIER MORENO M.D. Ph.D. GIUSEPPE LUMIA M.D. ALEJANDRA CARBONELL SAN ROMÁN M.D. TERESA SEGURA DE LA CAL M.D. ROBERTO MATÍA FRANCÉS M.D. Ph.D. ANTONIO HERNÁNDEZ MADRID M.D. Ph.D. JOSÉ LUIS ZAMORANO GÓMEZ M.D. Ph.D. 《Pacing and clinical electrophysiology : PACE》2015,38(9):1058-1065
5.
Unexpected Immunoresponse to Gal and APA Antigens in Diabetic Type 1 Patients Receiving Neonatal Pig Islets After 6 Years 总被引:1,自引:0,他引:1
Valdés-González RA Dorantes LM Garibay GN Bracho-Blanchet E Dávila-Pérez R Terán L Ormsby CE Ayala-Sumuano JT Copeman L White DJ 《Journal of clinical immunology》2007,27(3):266-274
Cotransplantation of porcine islets and Sertoli cells into preimplanted subcutaneous devices improve metabolic control in
type 1 diabetic patients, and survive grafted for more than 4 years. We report here, further assessment of the endocrine and
porcine nature of the surviving cells and the immune responses elicited toward Gal α(1,3)-Gal β(1,4)-GlcNAc (Gal) antigen
in patients who received a second and third transplants. No immunosuppressive drugs were administered. We were able to immunostain
insulin- and glucagon-positive cells in all biopsies of patients and Sertoli cell markers in 60.9% of biopsies. Additionally,
all biopsies tested, amplified the porcine COII gene. Patients demonstrated an increase in antipig antibodies in response
to the first transplant with a decreasing response toward the second and third transplants. In all transplants, the IgG levels
promptly returned to basal values after 3–4 months. The long-term survival of porcine cells and the reduced humoral immune
response to multiple transplants indicate a form of tolerance. We have not been able to find CD25-positive cells, indicating
that it is probably an immune accommodation of the graft. 相似文献
6.
PATRIZIA TENTI RITA ZAPPATORE SOLANGE ROMAGNOLI EMILIO CIVARDI PAULO GIUNTA ROBERTO SCELSI GIORGIO STELLA LUCIANO CARNEVALI 《The Journal of pathology》1996,178(1):65-70
Seventy-nine transitional cell carcinomas (TCCs) of the urinary bladder (25 grade 1, 22 grade 2, and 32 grade 3 tumours) were examined for p53 overexpression by immunohistochemistry with a monoclonal antibody and for human papillomavirus (HPV) infection by the polymerase chain reaction (PCR). Positive immunostaining for p53 was detected in 40·5 per cent of the cases; the percentage of positive cases was significantly lower in low-grade (G1 and G2) TCCs than in high-grade (G3) tumours (10·6 per cent vs. 84·4 per cent; P <0·0001). The overall rate of HPV infection was 32·9 per cent; 20·3 per cent of the cases were positive for HPV 16, 3·8 per cent for HPV 18, and 8·9 per cent for both. Consensus primers as well as type-specific primers for HPV types 6, 11, and 33 failed to detect any additional case with HPV infection. The prevalence of HPV 16 and/or HPV 18 infection was significantly higher in low-grade than in high-grade tumours (44·7 per cent vs. 15·6 per cent; P =0·0061). p53-positive cases were more common among papillary, deeply infiltrating tumours, and HPV-positive cases among papillary, non-infiltrating lesions. According to these data, p53 overexpression and HPV 16/18 infection are common findings in bladder TCC and there appears to be an inverse correlation of p53 overexpression and of HPV infection with tumour aggressiveness. The possibility of different molecular pathways in superficial low-grade and in invasive high-grade tumours is suggested. 相似文献
7.
Lissoni P Bonfanti A Bordin V Barni S Vigore L Ferrante R Rovelli F Fumagalli L 《Hematology (Amsterdam, Netherlands)》2000,5(2):117-125
Lymphocytosis is the main biomarker predicting the efficacy of subcutaneous IL-2 anticancer immunotherapy. In addition, it has been demonstrated the fundamental role of dendritic cells (DC) in the generation of an effective anticancer immunity. However, the relation between IL-2 and DC system needs to be further understood. This preliminary study was performed in an attempt to analyze changes in circulating DC during IL-2 cancer immunotherapy in relation to lymphocyte variations and clinical efficacy of treatment. The study included 20 metastatic renal cell cancer patients, who underwent subcutaneous low-dose IL-2 immunotherapy (6.000.000 IU/day for 6 days/week for 4 weeks). To evaluate DC, venous blood samples were collected before and after 2 weeks of IL-2 injections, corresponding to the period of maximum lymphocytosis. Immature (CD123(+) ) and mature (CD11c(+) ) DC were measured by FACS and monoclonal antibodies. IL-2 induced a significant increase in the mean number of circulating mature DC, whereas no substantial change occurred in immature DC mean number. The increase in mature DC was associated with a control of disease, whereas no rise was observed in patients who had progressed on IL-2 immunotherapy. Moreover, the increase in mature DC mean number was significantly higher in patients showing evident lymphocytosis, with lymphocyte enhancement greater than 1000 cells/mmc, than in patients with less pronounced lymphocytosis, even though no significant correlation was seen in between mature DC and lymphocyte increase. This preliminary study would suggest that IL-2 may stimulate DC system and that the clinical anticancer efficacy of IL-2 is associated with the increase in circulating mature DC, which could be considered as a new favourable biomarker during IL-2 immunotherapy. 相似文献
8.
CORNELIO UDERZO MARIA GRAZIA VALSECCHI ADRIANA BALDUZZI GIORGIO DINI ROBERTO MINIERO FRANCO LOCATELLI ROBERTO RONDELLI ANDREA PESSION WILLIAM ARCESE ANDREA BACIGALUPO PAOLA POLCHI MARINO ANDOLINA CHIARA MESSINA VALENTINO CONTER MAURIZIO ARICÓ STEFANIA GALIMBERTI & GIUSEPPE MASERA 《British journal of haematology》1997,96(2):387-394
We compared the outcome of children with high-risk acute lymphoblastic leukaemia (HR-ALL) in first complete remission (first CR) treated with chemotherapy (CHEMO) or with allogeneic bone marrow transplantation (BMT) in a multicentre study. All children treated by the Italian Paediatric Haematology Oncology Association for HR-ALL in first CR between 1986 and 1994 were eligible for the study. 30 children were given BMT at a median of 4 months from first CR, with preparative regimens including total-body irradiation ( n =25/30). 130 matched controls for BMT patients were identified among 397 HR-ALL CHEMO patients. Matching on main prognostic factors and duration of first CR was adopted to control the selection and time-to-transplant biases. The comparative analysis was based on the results of a stratified Cox model. The estimated hazard ratios of BMT versus CHEMO at 6 months, 1 year and 2 years after CR were 1.38 (CI 0.59–3.24), 0.69 (CI 0.27–1.77) and 0.35 (CI 0.06–1{\raise 5mu ..91), with an overall non-significant difference between the two groups ( P = 0.34). With a median follow-up of 4 years, the disease-free survival was 58.5% (SE 9.3) in the BMT group and 47.7% (SE 4.8) in the CHEMO group, at 4 years from CR. Non-leukaemic death occurred in 4% of CHEMO and 10% of BMT patients. In the BMT group the estimated cumulative incidence of relapse at 1.5 years from CR was 31.5% (SE 8.8) and did not change thereafter, whereas in the CHEMO group the corresponding figure was 29.2% (SE 4.1) and the incidence continued to increase thereafter (48.2% (SE 4.8) at 4 years from CR). The results of this study suggest that, with respect to the CHEMO group, the higher risk of early failure in the BMT group is outweighed by the lower risk of relapse after 1 year. Results prompt the need for a prospective study, in order to demonstrate the likely advantage of BMT in HR childhood ALL in first CR. 相似文献
9.
Intrapatient Comparison Between Chronic VVIR and DDD Pacing 'In Patients Affected by High Degree AV Block Without Heart Failure 总被引:2,自引:0,他引:2
CARLO MENOZZI MICHELE BRIGNOLE PIER VITTORIO MORACCHINI† GINO LOLLI MIRKA BACCHI MARIA CRISTINA TESORIERI† GIAN DOMENICO TOSONI† ROBERTO BOLLINI 《Pacing and clinical electrophysiology : PACE》1990,13(12):1816-1822
MENOZZI, C., ET AL.: Intrapatient Comparison Between Chronic VVIR and DDD Pacing in Patients Affected by High Degree AV Block Without Heart Failure. In patients affected by high degree AV block without preexisting congestive heart failure there is no definite demonstration that DDD pacing gives real clinical advantages in respect to VVIR pacing. We performed an intrapatient, long-term study between the two pacing modes in 14 high degree AV block patients, using the Medtronic Synergyst 7027 dual chamber pacemaker, who could be programmed alternatively in DDD or VVIR mode. After a 4-week run-in period following the pacemaker implant, patients completed a randomized, double-blind, cross-over study to compare the effect of 6-week period VVIR and DDD pacing on symptoms and cardiovascular parameters. A semiquantitative score scale was used to quantify the symptoms of general well-being, palpitations, dizziness, pulsating sensation in the neck or abdomen, shortness of breath at rest and during effort, chest pain, and NYHA classification. The sum of symptom scores was 10.4 ± 6.7 in VVIR period and 4.6 ± 2.7 in DDD period (p < 0.001); five patients (36%) crossed over early from VVIR to DDD because of intolerable symptoms; overall, eight patients preferred the DDD mode and no one preferred the VVIR. Cardiac output at rest (echo-Doppler method) was 4.7 ± 1.4 versus 5.7 ± 1.6 liter/min (p < 0.01), body weight was 65.9 ± 6.6 versus 64.9 ± 6.1 kg (p < 0.02), atrial natriuretic peptide was 236 ± 112 versus 198 ± 110 pg/mL (p < 0.01), respectively, during VVIR and DDD modes. Effort tolerance was similar with the two modes of pacing (68 ± 15 vs 70 ± 18 watt/min). In conclusion, hemodynamic advantages of atrial synchronization reflect a better quality of life for the patients even if an individual variability exists. 相似文献
10.
SEVERO SALVADORI MAURO MARASTONI GIANFRANCO BALBONI GIULIANO MARZOLA ROBERTO TOMATIS 《Chemical biology & drug design》1986,28(3):254-261
Dehydrophenylalanine having the Z-configuration (ΔPhe) and D-Phe were incorporated in positions 3 and/or 5 into dermorphin-(1–5)-peptide amide (H-Tyr-D-Ala-Phe-Gly-Tyr-NH2) in order to study the effect of structure or configurational changes. On GPI preparation, whereas the activity of [L-Phe5]-pentapeptide was fourfold higher than parent peptide and comparable to that of dermorphin, the substitution of Phe3 by its D-enantiomer was barely tolerated. The pentapeptides containing ΔPhe in positions 3 and/or 5 displayed even lower potency: particularly the unsaturation at position 3 alone or at position 3 and 5 was very detrimental to μ activity. 相似文献